Roasters and slow cookers are two types of cooking devices well known in the art. Roasters typically include a covered chamber lined by a metal pan for receiving the food to be cooked. The temperature controls permit a wide range of cooking temperatures that may be set to accommodate a particular recipe. Roasters typically permit temperatures as high as 500.degree. F. which is similar to that found in a typical kitchen oven. Roasters operate similar to a standard electric oven wherein the food is placed therein and cooked for a relatively short period of time, i.e., half an hour to two or three hours. Roasters include one or more heating elements that are capable of producing the high temperature required for roasting. Roasters typically include metal pan which hold the food. The metal pan fairly quickly and evenly distributes the heat thereby preventing the formation of localized hot spots.
Another type of cooking device well known in the art is a slow cooker. An example of such a device is marketed by the Assignee of this application under the trademark Crockpot.RTM.. Slow cookers typically include a stoneware or ceramic vessel for holding the food. The stoneware is typically removably insertable in a housing that contains heating elements for supplying heat to the stoneware and food. Slow cookers typically have a selector switch having a "high", "low" and "off" setting for varying the heat setting thereby affecting the cooking time.
The maximum power generated by slow cookers is significantly less then that for roasters since slow cookers rely on a slow even rate of cooking. Cooking time in slow cookers range from four to several hours. The low temperature cooking permits users of the device to start a meal cooking in the morning and have it ready and properly cooked in time for dinner. Due to the slow cooking nature of the device, the contents of the stoneware need not be constantly monitored in order to prevent burning such as with a roaster. In addition, the relatively low power and even distribution of heat of the slow cooker prevents any particular hot spot on the stoneware, which could lead to thermal stresses and cracking. The stoneware acts as an insulator which is beneficial for slow cooking but is susceptible to cracking if the heat output is too high and the temperature rises too quickly.
Roasters and slow cookers provide two very different ways to prepare food. The roaster with its high temperature range permits cooking meals within a relatively short time while the slow cooker allows simmering type cooking over several hours. Accordingly, it is desirable to have both a roaster and slow cooker in order to accommodate a wide variety of cooking situations. However, both of these units are relatively large counter top appliances and therefore either take up a large amount of kitchen counter top space or storage space in the kitchen. This particular problem is especially acute in small kitchens where the counter top space and storage is at a premium.
However, roasters of the prior art are unsuitable for safely slow cooking food in stoneware due to the high power output of such devices and the temperature sensitivity of stoneware. The control circuit of roasters typically includes a thermostat which turns on a heating element until a desired temperature level is reached and then the element is shut off. The cycling on and off of the heating element is used to control the temperature. Therefore, even on relatively low temperature settings a cooking vessel is subjected to a full power high heat condition that could damage stoneware. Accordingly, roasters almost exclusively include metallic inserts that are able to quickly distribute the heat and permit uniform cooking of the contents. In contrast, stoneware, which is essentially an insulator, does not dissipate heat well and is subject to cracking when exposed to fast temperature rises and high heat levels.
Accordingly, it would be desirable to provide a multipurpose cooking apparatus that selectively provides the cooking characteristics of both a roaster and a slow cooker.